Wire cloth and wire belts for use in paper making machines and method of making such wire cloth and wire belts



March 15, 1966 A. G. HOSE ET AL 3,240,635

WIRE CLOTH AND WIRE BELTS FOR USE IN PAPER MAKING MACHINES AND METHOD OFMAKING SUCH WIRE CLOTH AND WIRE BELTS Filed May 17, 1962 Fig. 2

INVENTORS Pump 6. Hose rmo BY Lnuazucs D. KUNSMHH H OIZNEYS UnitedStates Patent C "ice 3,240,635 WIRE CLOTH AND WIRE BELTS FOR USE IN PA-PER MAKING MACHINES AND METHOD OF MAKING SUCH WIRE CLOTH AND WIRE BELTSAlfred G. Hose, Cleveland, and Laurence D. Kunsman, Willoughby, Ohio,assignors to The Lindsay Wire Weaving Company, Cleveland, Ohio, acorporation of Ohio Filed May 17, 1962, Ser. No. 195,572 Claims. (Cl.148-123) This invention relates to wire cloth and woven wire belts whichare intended for use with paper making machines or the like and themethod of making the same.

In conventional practice, wire belts for use with Fourdrinierpaper-making machines are woven from softannealed warp and shute wires.The warp wires are normally comprised of Type C Phosphor bronzecontaining about 8% tin, 0.25% phosphorus, and the balance being copper.The shute wires are usually comprised of brass containing 15% to zinc,with the remainder being copper. The brass is utilized as a filler, andas such helps to absorb some of the demands put on the warp wires in thebelt. The warp wire must effectively withstand all of the tensile,fatigue, and wear demands put on the belt during its operation.

It has been experienced that wire belts for use in Fourdrinierpaper-making machines must have certain characteristics of porosity anduniformity as well as resistance to damage, fatigue failure, Wear, andcorrosion in order to provide the optimum desired operational conditionswhen used on such paper-making machines. Heretofore, Fourdrinier beltshave been found to be prone to damage during operation, and such damagelimits the useful wear life of a wire belt. Many efforts have been madeto weave wire belts characterized by having a greater resistance todamage, but the attainment of such properties have been limited by thesoft-condition of the warp and shute wires, from which it has been foundnecessary to Weave Fourdrinier wire belts.

In the past, the composition of the warp and shute wire alloys have beenvaried to gain increases in such properties as elastic modulus, whereasvarious weaving configurations have been attempted, and a variety ofchanges have been made in warp and shute wire sizes in attempts toimprove resistance to damage. For example, stainless wire alloys, whichhave an elastic modulus of nearly twice that of the conventionally usedPhosphor bronze and brass have been woven into belts but have failed toshow superior resistance to damage. Similarly, other high modulusalloys, such as nickel and Monel, have also been used, but have beenfound to equally be unsatisfactory. Consequently, attempts to improveresistance to damage have been limited to only those gained by changesin alloy composition and not in the treatment to the alloy, other thanchanges in soft annealing practices and changes in the manner ofWeaving.

While it is understood that the weaving process causes basic alterationsto the internal structure of the warp wire at the knuckles (crimps),that part of the warp not involved in the crimp radius, receives noalteration. This part consists of the entire bottom knuckle and thesloped approach to the top knuckle. The alterations mentioned cause somestrain-hardening to take place, but at the expense of loss incross-section. Thus, the hardening effect due to weaving is not uniformand becomes diminished, in a characterized manner, by the stretchingwhich takes place in forming the crimps or knuckles.

Additionally, the shute wire, which, While essentially a filler wire, isnevertheless, a component from which the wire cloth must derive part ofits strength and resistance to damage. It is weakened by the weavingaction, which Patented Mar. 15, 1966 partially shears its diameter anddistorts it into a configuration not unlike a notched, twisted column.The shute wire cannot, therefore, be expected to add significantly toLhe total strength and damage resistance of a conventional elt.

We have found, however, that by weaving wire cloth from heat-treatablewire alloys in the annealed state, finishing the cloth so woven into abelt, and then subjecting the belt to a heat treatment, that the belthas a substantially improved resistance to damage. Additionally, We havefound that other properties, such at fatigue, wear and corrosionresistance, may also be improved, depending upon the degree of heattreatment and choice of warp and shute alloy composition amenable tosuch heat treatment.

Accordingly, a primary object of the present invention is to provide awire cloth as Well as a method of making such cloth, and adapted for usewith paper making machines having improved resistance to damage, fatiguefailure, wear and corrosion.

Another object of the present invention is to provide a wire cloth madeprimarily from a precipitation hardenable alloy composition as well asthe method of making such cloth, adapted for use with paper-makingmachines having improved resistance to damage, fatigue failure, wear andcorrosion.

A still further object of the present invention is to pro vide a wirebelt, as well as the method of making such belt, and adapted for usewith paper-making machines having improved resistance to damage, fatiguefailure, wear and corrosion.

A further object of the present invention is to provide a wire belt madeprimarily from precipitation hardenable alloys as well as the method ofmaking such belt, adapted for use in paper-making machines havingimproved resistance to damage, fatigue failure, wear and corrosion.

An additional object of the present invention is to provide a method oftreating wire cloth, endless belts or the like, made primarily fromprecipitation hardenable alloy compositions, and adapted for use withpaper-making machines having improved resistance to damage, fatiguefailure, wear and corrosion.

Other and further objects of the present invention will be apparent fromthe following description and claims, and are illustrated in theaccompanying drawings, which, by way of illustration, show a preferredembodiment of the present invention, and the principles thereof, andwhat is now considered to be the best mode in which to apply theseprinciples.

Other embodiments of the invention embodying the same or equivalentprinciples may be applied by those skilled in the art, and structuralchanges may be made, as desired, without departing from the scope of thepresent invention.

In the drawings:

FIG. 1 is a perspective View of the wire cloth of the present inventionformed into an endless belt by means of a conventional seam adapted foruse with paper making machines;

FIG. 2 is a diagrammatic view of the wire cloth of the present inventionmounted on rollers and intermediately passing through a heat treatingfurnace.

For purposes of illustration, the preparation of the warp and shutewire, from which such an improved belt may be made, may normally becarried out by drawing the wire down to a finished size from anintermediate wire size, and subjecting the wire to a solution heattreatment. Generally speaking, the solution heat-treatment may vary withthe condition and character of the alloy composition and may normally becarried out at a temperature and rate sufficient to secure the desiredductility and yield strength suitable for weaving into a wire cloth.

In the woven condition, the wire cloth is preferably subjected tocontrolled age-hardening operations. In such case, the wire cloth mayfirst be seamed by suitable brazing operations into an endless belt, asnoted generally at 1 of FIG. 1. Having installed the scam, the endlessbelt may then be moved to a stretcher 2 (FIG. 2) where stretcher rolls 3and 4 are adapted to stretch the belt to the desired paper machinelength. In some cases, where slight irregularities appear on the surfaceof the belt, it may be desirable to smooth the belt down in those areasin the customary manner, and such smoothing operations may be alsoapplied after heat treatment, if necessary. To commence theage-hardening heat treatment, the belt may be moved slowly over thestretcher rolls (3 and 4) through a suitable heat-treating furnace, suchas shown generally at 5, and heated at a temperature and at a ratesufficient to cause the desired amount of hardening of the warp andshute wires. The belt may then be cooled to room temperature. Thisheating cause-s internal structural changes in the warp and shute wireresulting in a hardening of the wire, which is manifest in an increasein tensile strength, fatigue life, wearability, and damage resistance ofthe belt.

As the precipitation-hardening of the alloy composition comprising thewire depends upon temperature, as well as upon time, there may beseveral treatments which produce the desired characteristics of a beltsuitable for use with paper making machines. Additionally, optimumage-hardening characteristics depend upon the composition of the alloyand to some extent upon its structural condition; that is, upon theamount of prior mechanical working of the metal.

Accordingly, in one form of this embodiment, the warp and shute wireswhich may be comprised of a Berylco 25 alloy, may be cold drawn from anintermediate size down to a finished wire size of from 0.0031 inch to0.013 inch and solution heat-treated to secure the desired yield andtensile strength suitable for weaving. In this form, the yield strengthof the Berylco 25 warp would be about 45,000 p.s.i. at a tensilestrength of about 67,000 pounds per inch of width with an elongation ofabout 50% in 5 inches. The Berylco 25 shute would have a yield strengthof about 35,000 p.s.i. and a tensile strength of about 47,000 pounds perinch of width with an elongation of about 36% in 5 inches.

The warp and shute wires may then be woven into a 56-36 mesh wire clothin the normal manner. As woven, the warpwise tensile strength of thecloth was found to be about 248 pounds per inch (in width) with awarpwise bending fatigue resistance of about 12,000 (cycles to failure).In the as-woven condition, the wire cloth may then be subjected to anage-hardening by heating to a temperature of from 475-650 F. and holdingat such temperature for a period of A to 3 hours to cause the necessaryincrease in the desired amount of tensile strength. The wire cloth maythen be air cooled to room temperature. After such heat treating, thewarpwise tensile strength was found to be about 300 pounds per inch witha warpwise bending fatigue resistance of about 16,000 (cycles tofailure).

Additional increases in fatigue life as well as improved uniformity ofproperty gains may be achieved by an alternative intermediatesolution-annealing treatment carried out between the weaving andage-hardening operations. In this form, after weaving the wire, intocloth, the cloth may be rolled onto a heat-resistance pole, heated toabout 1475 F. and held at such temperature for about minutes. The wirecloth may then be water quenched as rapidly as possible to retain thesolid solution of beryllium in copper. Another method by which thistreatment may be effected is by the heating of the wire cloth to about1475 F. as it is unrolled through the furnace, and subjecting the wirecloth to a water quenching operation as it emerges continuously from thefurnace. Rerolling of the wire cloth may then be accomplished for thepurpose of seaming and finishing the wire cloth into a belt, after whichthe age-hardening treatment may be undertaken to cause the desiredimprovement in properties. It is to be understood, however, that suchadditional solutionannealing treatment may be applied to the belt, aswoven, in passing through a suitable heat treating furnace (FIG. 2) tocause the desired improvement in properties.

For the purpose of disclosure, the nature of the intermediatesolution-annealing treatment, which is stabilized by the water quenchingoperation is such that the effects of heterogenous straining of thestructure during weaving is eliminated. This allows a uniformage-hardening to occur, thus increasing the fatigue life of the wirebelt to a level beyond 16,000 cycles to failure. In this embodiment, thecomposition of such Berylco 25 alloy may be as follows:

Percent Beryllium 1.80-2.25 Cobalt 0.18-0.30

Copper Balance Similarly, in another form of this embodiment, the warpand shute wires, which may be comprised of Elgiloy alloy, may be coldreduced from an intermediate size down to a finished wire size of about0.0031 inch to 0.013 inch. Hereagain, the wire may be subjected to asolution heat-treatment to secure the desired yield and tensile strengthsuitable for weaving. The warp and shute wires may then be woven into a56-36 mesh wire cloth in the normal manner. The yield strength of theElgiloy warp would be about 60,000 p.s.i. at a tensile strength about110,000 pounds per inch of width with an elongation of about 50% in 5inches. The Elgiloy shute would have a yield strength of about 50,000p.s.i. at a tensile strength of about 95,000 pounds per inch of widthwith an elongation of about 60% in 5 inches.

The warp and shute wires may then be woven into a 56-36 mesh wire clothin the normal manner. As woven, the warpwise tensile strength of thecloth is about 250 pounds per inch (in width) with a warpwise bendingfatigue resistance of about 9,600 (cycles to failure). Having performedthe desired seaming and stretching operations, the wire belt may then besubjected to a heating or age-hardening at a temperature of 600-1000 F.and held for a period of about 3-5 hours to effect the desired increasein properties. The wire belt may then be aircooled to room temperature.In the finished and heattreated condition, the warpwise tensile strengthof the wire belt is about 500 pounds per inch (in width) with a warpwisebending fatigue resistance of about 31,000 (cycles to failure). Thecomposition of such Elgiloy alloy may be as follows:

Percent Cobalt 40 Chromium 20 Nickel 15 Molybdenum 7 Manganese 2 Carbon0.15 Beryllium 0.04 Iron Balance For purposes of disclosure, whenreference is made to the alloy composition of the warp and shute wires,we refer to those alloys which are age-hardenable. In this respect, andby way of specific example we have found the alloy composition ofBerylco 25 and Elgiloy to yield highly satisfactory results. It is to beunderstood, however, that other age-hardenable alloy compositions willproduce similar beneficial results. For example, we have found that 17-7PH stainless steel, comprising 16.0 to 18.0% chromium, 6.5 to 7.5%nickel, 0.9% carbon, 0.75 to 1.50% aluminum with the balance being iron,will provide equally beneficial results in producing a woven wire beltsuitable for use with paper making machines. In this connection, it isto be understood that the warp and shute wires may be of the same alloycomposition in each case, or the warp and shute wires may be ofrespectively different but compatible alloy compositions in each case,modified only slightly in yield and tensile strength to weave properly.

In accordance with the foregoing description, it will be apparent thatthe wire belt of the present invention not only possesses the novelcharacteristics of resistance to damage, but also resistance to wear,fatigue and corrosion. Resistance to fatigue becomes exceedinglyimportant in present paper making operations, wherein paper makingmachine speeds in many cases exceeds over 2000 feet per minute.Consequently, as machine speeds increase the wire belt must havesufficient bend resistance if it is not to fail from fatigue-crackinglong before it is actually worn out. Furthermore, increased life of thewire belt of the present invention provides a substantial economicsaving, not only from a material standpoint with respect to the beltsthemselves, but also form from an operational standpoint, due to therelatively low replacement cost of such improved belts.

Thus, while we have illustrated herein a preferred embodiment of ourinvention, it is to be understood that changes and variations may bemade by those skilled in the art without departing from the spirit andscope of the appended claims.

We claim:

1. In the process for making Fourdrinier wire cloth having interwovensets of Warp and shute wires made from precipitation hardenable metalalloys selected from the group consisting of copper-beryllium-cobaltalloys, iron-nickel-chromium-cobalt alloys, and iron-chromium alloys,the improvement comprising the steps of subjecting the wire as woven toa precipitation hardening, said precipitation hardening comprisingheating the wires to a temperature of between about 475 F. to 1000 F.for a period of time ranging between about one-fourth to five hours, andthen cooling the wires to room temperature to provide in the hardenedcloth a warpwise tensile strength of between about 300 lbs. to 500 lbs.per inch of width, and a warpwise bending fatigue resistance of betweenabout 16,000 to 31,000 cycles to failure.

2. In the process for making Fourdrinier wire cloth having interwovensets of warp and shute wires made from precipitation hardenable metalalloys selected from the group consisting of copper-beryllium-cobaltalloys, iron-nickel-chromium-cobalt alloys, and iron-chromium alloys,the improvement comprising the steps of subjecting the wires to asolution-heat treatment and quenching the wires to an unhardenedcondition, forming the unhardened wires into the desired wovenconstruction, subjecting the wires as woven to a precipitation hardeningby heating the wires to a temperature of between about 475 to 1000 F.for a period of time ranging between about one-fourth to five hours, andthen cooling the wires at a temperature and rate sufficient to providein the woven and hardened condition of the cloth a warpwise tensilestrength of between about 300 lbs. to 500 lbs. per inch of width and awarpwise bending fatigue resistance of between about 16,000 cycles to31,000 cycles to failure.

3. In the process for making Fourdrinier wire cloth having interwovensets of warp and shute wires made from precipitation hardenablecopper-beryllium-cobalt alloys, the improvement comprising the steps ofsubjecting the wire as woven to a precipitation hardening, saidprecipitation hardening comprising heating the wires to a temperaturebetween about 475 F. to 650 F. for a period of time ranging betweenabout A to 3 hours, and then cooling the wires to room temperature toprovide in the hardened cloth a warpwise tensile strength of about 300lbs. per inch of width and a warpwise bending fatigue resistance ofabout 16,000 cycles to failure.

4. A process in accordance with claim 3, wherein the warp and :shutewires are subjected to a solution heat 'treatment prior to saidprecipitation hardening, said solution heat treatment comprising heatingthe wire to a temperature of about 1,475 E, for a period of time ofabout 15 minutes, and then quenching the wire.

5. A process in accordance with claim 3, wherein the precipitationhardenable alloy has a composition comprising, by weight, beryllium from1.80% to 2.25%, cobalt from 0.18% to 0.30%, and substantially all of thebalance being copper.

6. In the process for making Fourdrinier wire cloth having interwovensets of warp and shute wires made from precipitation hardenableiron-nickel-chromiumcobalt alloys, the improvement comprising the stepsof subjecting the wire as woven to a precipitation hardening, saidprecipitation hardening comprising heating the wires to a temperature ofbetween about 600 F. to 1,000 F. for a period of time ranging betweenabout 3 to 5 hours, and then cooling the wires to room temperature toprovide in the hardened cloth a warpwise tensile strength of about 500pounds per inch of width with a warpwise bending fatigue resistance ofabout 31,000 cycles to failure.

7. A process in accordance with claim 6, wherein the warp and shutewires are subjected to a solution heat treatment prior to saidprecipitation hardening, said solution heat treatment comprising heatingthe wire to a temperature of about 1,475 F. and for a period of time ofabout 15 minutes and then quenching the wire.

8. A process in accordance with claim 6, wherein the precipitationhardenable alloy has a composition comprising, by weight, about 40%cobalt, 20% chromium, 15% nickel, 7% molybdenum, carbon from trace toabout 0.15%, beryllium from trace to about 0.04%, and substantially allof the balance being iron.

9. A process for making an endless belt for use with paper makingmachines, having interwoven sets of warp and shute wires made fromprecipitation hardenable copperberyllium-cobalt alloys, the stepsincluding reducing the warp and shute wires from an intermediate wiresize down to a finished wire size, heating the warp and shute wires to atemperature of about 1,475 F., for a period of time of about 15 minutesand quenching the wires to secure a predetermined yield and tensilestrength suitable for forming into wire cloth, weaving the warp andshute wires into a woven wire cloth, joining the ends of the woven wirecloth together to form an endless belt, heating the endless belt to atemperature of about between 475 F. to 650 F. for a period of timeranging between M: and 3 hours and cooling the belt to room temperatureto provide in the hardened belt a warpwise tensile strength of about 300lbs. per inch of width with a warpwise bending fatigue resistance ofabout 16,000 cycles to failure.

10. A process for making an endless belt for use with paper makingmachines having interwoven sets of warp and shute wires made fromprecipitation hardenable ironnickel-chromium-cobalt alloys, the stepsincluding reducing the warp and shute wires from an intermediate wiresize down to a finished wire size, heating the warp and shute wires to atemperature of about 1,475 F. for a period of time of about 15 minutesand quenching the wires to secure a predetermined yield and tensilestrength suitable for forming into wire cloth, weaving the warp andshute wires into a woven wire cloth, joining the ends of the woven wirecloth together to form an endless belt, heating the endless belt to atemperature between about 600 F. to 1,000 F. for a period of timeranging between about 3 to 5 hours, and then cooling the wire to roomtemperature to provide in the hardened belt a warpwise tensile strengthof about 500 lbs. per inch of width with a warpwise bending fatigueresistance of about 31,000 cycles to failure.

11. A wire belt for use with paper making machines, having interwovensets of warp and shute wires made from a precipitation hardenablecopper-beryllium-cobalt alloy, heated as woven to a temperature betweenabout 475 F. to 650 F. for a period of time ranging between about A to 3hours, and cooled to room temperature to provide in the belt a warpwisetensile strength of about 300 pounds per inch of width and a warpwisebending fatigue resistance of about 16,000 cycles to failure.

12. A wire belt in accordance with claim 11, wherein the precipitationof hardenable alloy has a composition comprising, by weight, berylliumfrom 1.80% to 2.25%, cobalt from 0.18% to 0.30%, and substantially allof the balance being copper.

13. A Wire belt for use in paper making machines having interwoven setsof warp and shute wires made from a precipitation hardenableiron-nickel-chromium-cobalt all-y, heated as woven to a temperaturebetween about 600 F. to 1,000 P. for a period of time ranging between 3to 5 hours, and cooled to room temperature to provide in the hardenedbelt a warpwise tensile strength of about 500 pounds per inch of widthand a warpwise bending fatigue resistance of about 31,000 cycles tofailure.

14. A wire belt in accordance with claim 13, wherein a precipitationhardenable alloy has a composition comprising, by weight, about 40%cobalt, 20% chromium, 15% nickel, 7% molybdenum, carbon from trace toabout 0.15%, beryllium from trace to about 0.04% and substantially allof the balance being iron.

15. A wire belt for use in paper making machines having interwoven setsof warp and shute wires made from precipitation hardenable alloysselected from the group consisting of copper-beryllium-cobalt alloys,iron- 5 nickel-chromium-cobalt alloys, and iron-chromium alloys, heatedas woven to a temperature between about 475 F. to 1000 F. for a periodof time ranging between about one-fourth to five hours and cooled toroom temperature, to provide in the hardened belt a warpwise tensilestrength 10 of between about 300 lbs. to 500 lbs. per inch of width anda warpwise bending fatigue resistance of between about 16,000 to 31,000cycles to failure.

References Cited by the Examiner UNITED STATES PATENTS 1,975,114 10/1934Masing et al. 148-l60 2,088,449 7/1937 Specht 2458 2,288,512 6/1937Buchanan 2458 2,422,477 6/1947 Driver 14816O 2,482,098 9/1949 Clarke148135 2,859,149 11/1958 Straumann 148-123 2,908,065 10/1959 Hinz 245-102,958,618 11/1960 Allen 148-135 DAVID L. RECK, Primary Examiner.

HYLAND BIZOT, Examiner.

9. A PROCESS FOR MAKING AN ENDLESS BELT FOR USE WITH PAPER MAKINGMACHINES, HAVING INTERWOVEN SETS OF WARP AND SHUTE WIRES MADE FFOMPRECIPITATION HARDENABLE COPPER-BERYLLIUM-COBALT ALLOYS, THE STEPSINCLUDING REDUCING THE WARP AND SHUTE WIRES FROM AN INTERMEDIATE WIRESIZE DOWN TO A FINISHED WIRE SIZE, HEATING THE WARP AND SHUTE WIRES TO ATEMPERATURE OF ABOUT 1,475*F., FOR A PERIOD OF TIME OF ABOUT 15 MINUTESAND QUENCHING THE WIRES TO SECURE A PREDETERMINED YIELD AND TENSILESTRENGTH SUITABLE FOR FORMING INTO WIRE CLOTH, WEAVING THE WARP ANDSHUTE WIRES INTO A WOVEN WIRE CLOTH, JOINING THE ENDS OF THE WOVEN WIRECLOTH TOGETHER TO FORM AN ENDLESS BELT, HEATING THE ENDLESS BELT TO ATEMPERATURE OF ABOUT BETWEEN 475*F. TO 650*F. FOR A PERIOD OF TIMERANGING BETWEEN 1/4 AND 3 HOURS AND COOLING THE BELT TO ROOM TEMPERATURETO PROVIDE IN THE HARDENED BELT A WARPWISE TENSILE STRENGTH OF ABOUT 300LBS. PER INCH OF WIDTH WITH A WARPWISE BENDING FATIGUE RESISTENCE OFABOUT 16,000 CYCLES TO FAILURE.
 10. A PROCESS FOR MAKING AN ENDLESS BELTFOR USE WITH PAPER MAKING MACHINES HAVING INTERWOVEN SETS OF WARP ANDSHUTE WIRES MADE FROM PRECIPITATION HARDENABLEIRONNICKEL-CHROMIUM-COBALT ALLOYS, THE STEPS INCLUDING REDUCING THE WARPAND SHUTE WIRES FROM AN INTERMEDIATE WIRE SIZE DOWN TO A FINISHED WIRESIZE, HEATING THE WARP AND SHUTE WIRES TO A TEMPERATURE OF ABOUT1,475*F. FOR A PERIOD OF TIME OF ABOUT 15 MINUTES AND QUENCHING THEWIRES TO SECURE A PREDETERMINED YIELD AND TENSILE STRENGTH SUITABLE FORFORMING INTO WIRE CLOTH, WEAVING THE WARP AND SHUTE WIRES INTO A WOVENWIRE CLOTH, JOINING THE ENDS OF THE WOVEN WIRE CLOTH TOGETHER TO FORM ANENDLESS BELT, HEATING THE ENDLESS BELT TO A TEMPERATURE BETWEEN ABOUT600*F. TO 1,000*F. FOR A PERIOD OF TIME RANGING BETWEEN ABOUT 3 TO 5HOURS, AND THEN COOLING THE WIRE TO ROOM TEMPERATURE TO PROVIDE IN THEHARDENED BELT A WARPWISE TENSILE STRENGTH OF ABOUT 500 LBS. PER INCH OFWIDTH WITH A WARPWISE BENDING FATIGUE RESISTANCE OF ABOUT 31,000 CYCLESOF FAILURE.